Pump

ABSTRACT

Pump, comprising a casing, pumping teeth solid with a pumping wheel, sealing teeth solid with a sealing wheel, the pumping teeth and the sealing teeth moving in annular spaces which are separated along a portion of their length and do intersect along another portion of their length; part of that contour of the sealing teeth and that surface of the disc or ring of the pumping wheel which effect the sealing between the suction zone and the pressure zone being parts of two substantially spherical surfaces with common center and substantially equal radii; and the arrangement of the pumping wheel and sealing wheel being such that their respective axis do intersect in the center of the spherical surfaces described above.

United States atent [72] Inventor Gavril T. Lusztig 21 Appl. No. 848,225122 Filed Aug. 7, 1969 I45] Patented Nov. 23, 1971 [73] Assignee GavrllT. Lusztig 80 Lupton Lane Apt. 1C, Haledon, NJ. 07508 [54] PUMP 10Claims, 4 Drawing Figs.

[52] U.S.C1 418/195, 418/196 [51] 1nt.C1 F0lc1/08, FO4c 1/04, F04c 17/04[50] Field ofSearch 418/195, 10,196; lO3/l25,l27, 1l7;230/l37,142, 150;91/69, 85; 123/12C, 12 E [56] References Cited UNITED STATES PATENTS1,284,768 11/1918 Powell 91/85 2,679,352 5/1954 Vance... 230/1373,335,669 8/1967 Gerber 103/127 Primary li.\-aminerCarlton R. CroyleAssislan! Examiner-John J. Vrablik Atmrne v.1ames E. Niles ABSTRACT:Pump, comprising a casing, pumping teeth solid with a pumping wheel,sealing teeth solid with a sealing wheel, the pumping teeth and thesealing teeth moving in annular spaces which are separated along aportion of their length and do intersect along another portion of theirlength; part of that contour of the sealing teeth and that surface ofthe disc or ring of the pumping wheel which efiect the sealing betweenthe suction zone and the pressure zone being parts of two substantiallyspherical surfaces with common center and substantially equal radii; andthe arrangement of the pumping wheel and sealing wheel being such thattheir respective axis do intersect in the center of the sphericalsurfaces described above.

PATENTEUNUV 23 I911 3,622,255

' SHEET 2 OF 2 PUMP Various pumps are known in the prior art, whichpresent the common feature of a casing containing cavities in which anumber of two or more wheels with meshing teeth are disposed. One ormore wheels work as pumping wheels, the teeth of these wheels will becalled hereinafter pumping teeth; the remaining wheels work as sealingwheels, the teeth of these wheels will be called hereinafter sealingteeth.

The cavities in the casing are partially filled out by the discs orrings which carry the pumping teeth and the sealing teeth; and by thepossibly present other parts which can be fixed or rotatable togetherwith the wheels in such way that there remain empty annular spaces, inwhich the pumping teeth and the sealing teeth move during the rotationof the wheels. The annular space in which the pumping teeth move andthose in which the sealing teeth move are completely separated along aportion of their length, and along another portion of their length theyare intersecting, such that during the rotation of the wheels thepumping teeth enter in the annular space in which the sealing teethmove, then the pumping teeth move a distance being completely immersedin the space in which the sealing teeth move contained in the spacesbetween the sealing teeth, and then leave that space.

In the portion in which the pumping teeth enter in the spaces betweenthe sealing teeth the fluid is expelled, this portion being calledhereinafter pressure zone, and communicates to the pressure port; in theportion in which the pumping teeth leave the spaces they hold betweenthe sealing teeth, the fluid is aspirated; this portion being calledhereinafter suction zone, and communicates to the suction port.

The sealing of the suction zone from the pressure zone occurs in thedirection of the rotation of the wheels by means of the pumping teethand the sealing teeth, the contours of which are fitted with smallclearance in respect to the corresponding surfaces of the casing. It isalso essential for the sealing that the discs or rings of the pumpingand sealing wheels are fitted with small clearance between their lateralsurfaces and the corresponding surfaces of the casing. Contrary to thedirection of the rotation, the sealing of the suction zone from thepressure zone occurs by means of the sealing teeth, the contours ofwhich are fitted with small clearance in respect to the correspondingsurfaces of the casing, and in respect to the corresponding surfaces ofthe disc or ring of the pumping wheel, or with a possibly present disc,which is rotating together with the pumping wheel and lateral with thecasing.

In the prior art, the sealing between the sealing teeth and the surfaceof the disc or ring of the pumping wheel or of the possibly present discwhich is rotating together with the pumping wheel, occurs along planesurface (s). That implies the disadvantage of limiting the choice of thearrangement of the wheels; and especially the compensation of thehydraulic pressure-load upon the wheels becomes impossible orunfeasible, and could be achieved only by introducing otherdisadvantages, especially the augmentation of the volumetric losses.

According to the present invention, that part of the contours of thesealing teeth, and that surface of the disc(s) or ring(s) of the pumpingwheel(s), and sometimes also of the casing, which are fitted with smallclearance to effect the sealing between the suction zone and thepressure zone are portions of two substantially spherical surfaces withcommon center of curvature and substantially equal radii, the radiidiffering only slightly for forming the necessary running clearancebetween the surfaces in relative motion. Also according to the presentinvention, the arrangement of the pumping wheel(s) and of the sealingwheel(s) is such that their respective axis do intersect in the centerof curvature of the spherical surfaces described above.

One important feature of the present invention resides in theaccomplishment of the sealing between the moving parts usingsurface-contacts (respective gaps) between them, thus avoiding the poorsealing efiects of the customary linear sealing-line design.

Another important feature resides in the possibility to compensate thehydraulic-pressure loads upon the wheels by using adequate arrangements.

These and other features of the invention will emerge clearly from thepreferred embodiments described in connection with the drawings, inwhich:

FIG. 1 is a longitudinal cross-sectional view of the pump or motor.

FIG. 2 is a partial sectional view taken along a spherical surfacethrough a suction zone and a pressure zone of the pump or motor shown inFIG. 1.

FIG. 3 is a longitudinal cross-sectional view of a similar sump or motoras shown in FIG. 1 having a relatively wide disc of the pumping wheel.

FIG. 4 is a longitudinal cross-sectional view of a pump or motor havingtwo sets of pumping teeth.

Following is a description of the pump or motor shown in FIG. 1:

A casing, 1, contains cavities which are partially filled out by a disc,2, a shaft, 3, a key, 4, and a ring, 5. In the remaining empty annularspaces are disposed the pumping teeth 6 solid with the disc 2 and thesealing teeth 7 solid with the ring 5. Further cavities 8 and 9 areprovided in the casing 1, which respectively connect the suction zonesand the pressure zones to the corresponding ports. A pumping wheelconsists of the disc 2 and the pumping teeth 6 solid with it. A sealingwheel consists of the ring 5 and the sealing teeth 7 solid with it. Theaxis 11 of the pumping wheel and the axis 12 of the sealing wheel areintersecting in a point which is at the same time the center ofcurvature of the spherical surface 13 of the disc 2 and of the sphericalsurface 14 of the contour of the sealing teeth 7. A key 10 is providedto connect the shaft 3 with a driving device not shown in the drawings.The arrows 15 and 16 are indicating the direction of the motion of thepumping teeth and the sealing teeth; the arrows l7, l8, l9 and 20 areindicating the flow of the pumped fluid. The shaft 3, the pumping wheeland the sealing wheel are rotatable in respect to the casing. The shaft3 being driven, the pumping wheel is turning together with it and thepumping teeth 6 shown in the partial section represented in FIG. 2 movefor instance in the direction indicated by the arrow 15. The meshingsealing teeth 7 are pushed by the pumping teeth 6 and move in thedirection indicated by the arrow 16; this causes the rotation of thesealing wheel.

In the situation shown in FIG. 2, following the direction indicated bythe arrows l5 and 16, the annular spaces in which the pumping teeth moveand that in which the sealing teeth move are first separated, then theyare intersecting and finally separated again. In the portion in whichthe pumping teeth 6 enter in the annular space in which the sealingteeth 7 move the fluid is expelled, this being indicated by the arrowsl9 and 20. This portion being a pressure zone, it communicates to thepressure port (not shown in the drawings). In the portion in which thepumping teeth 6 leave the spaces they held between the sealing teeth 7,the fluid is aspirated, this being indicated by the arrows l7 and 18.This portion being a suction zone, it communicates to the suction port(not shown in the drawings).

The sealing of the suction zone from the pressure zone occurs in thedirection of the movement indicated by the arrows l5 and 16 of thepumping teeth 6 and sealing teeth 7 by means of the pumping teeth 6 andthe sealing teeth 7, the contours of which are fitted with smallclearance in respect to the corresponding surfaces of the casing l. Thesealing is completed by the fit with small clearance of the lateralsurfaces of the disc 2 and ring 5 in respect to the correspondingsurfaces of the casing l.

Contrary to the direction of the movement of the pumping teeth 6 andsealing teeth 7, the sealing of the suction zone from the pressure zoneoccurs by means of the sealing teeth 7, the tops of which have accordingto this invention spherical surfaces 14 which are fitted with smallclearance in respect to the also spherical surface 13 of the disc 2 andthe also spherical surface of the casing i, which forms small gaps withthe spherical surface 14 of the tops of the sealing teeth 7. The sealingis completed by the fit with small clearance of the lateral surfaces ofthe sealing teeth 7 and the lateral surfaces of the disc 2 and ring inrespect to the corresponding surfaces of the casing l.

The pump shown in FIG. 3 works basically on the same idea as that shownin the FIG. 11. The parts In to 14a shown in FIG. 3 are homologous tothe parts 1 to 14 shown in FIG. 1. The disc in of the pump shown in FIG.3 is, however, substantially wider than the disc 2 of the pump shown inFIG. 1. Because this difference in the case of the motor shown in FIG. 3the sealing of the suction zone from the pressure zone occurs in thedirection of the movement of the pumping teeth 6a and sealing teeth 7aby means of the pumping teeth 6a and the sealing teeth 7a, the contoursof which are fitted with small clearance in respect to the correspondingsurfaces of the casing in and in respect to the corresponding surface ofthe disc la. The sealing is completed by the fit with small clearance ofthe lateral surfaces of the disc in and ring 50 in respect to thecorresponding surface of the casing in and by the fit with smallclearance between the surface 13a of the disc Ia and the correspondingsurface of the casing la.

Contrary to the direction of the movement of the pumping teeth 6a andsealing teeth 7a, the sealing of the suction zone from the pressure zoneoccurs by means by the sealing teeth 7a, the tops of which haveaccording to this invention, spherical surfaces 14a which are fittedwith small clearance in respect to the also spherical surface 13a of thedisc 20. The scaling is completed by the fit with small clearance of thelateral surfaces of the sealing teeth 7a and the lateral surfaces of thering 5a in respect to the corresponding surfaces of the casing Ia.

In both of the preferred embodiments described, the hydraulicpressure-loads upon the pumping wheel and the sealing wheel arecompensated, because in both of the described embodiments there are twodiametrically opposed pressure zones, and the pressure forces appliedupon the wheels in the area of the one and the opposite zone are equalin value and have opposite directions, thus compensating one the other.

While the described embodiments present two particular cases of thewidth of the disc of the pumping wheel (6 and 6a it is understood thatthe width of that disc can have any other suitable value.

It is also understood that, while in the described embodiments theannular space in which the pumping teeth. move and the annular space inwhich the sealing teeth move do intersect in two diametrically oppositeareas; by changing the relative position of the annular spaces,arrangements can be obtained in which said two annular spaces dointersect in two areas which are not diametrically opposed, orarrangements in which they intersect in one area only.

It is also understood that while in the described embodiments thepumping teeth are solid with a disc and the sealing teeth are solid witha ring, arrangements can be provided in which the pumping teeth aresolid with a ring and the sealing teeth are solid with a disc.

It is also understood that while each of the described embodimentscontains one set of pumping teeth and one set of sealing teeth,arrangements can be provided containing more than one set of pumpingteeth and/or more than one set of sealing teeth In FIG. 4 is shownanother embodiment which works basically on the same idea as that shownin FIG. 3. The parts lb to 14b, shown in FIG. 4 are homologous to theparts In to Me shown in FIG. 3. However, the pump shown in FIG. 4comprises two sets of pumping teeth 6b] and 6b2 solid with the disc 21;,and the annular space in which the pumping teeth 6b! move does intersectthe annular space in which the sealing teeth 7bmove in one area, and theannular space in which the pumping teeth 6b2 move does intersect theannular space in which the sealing teeth 7b move also in one area,diametrically opposed to the area in which the annular space in whichthe pumping teeth 61 move does intersect the annular space in which thesealing teeth 7b move.

It is also understood that the described arrangement can be 5 also usedas fluid motor, flow meter, mixing device or in any other purpose suitedby this invention.

I claim:

l. A rotary pump comprising a casing having a number of cavitiesconnected by annular spaces having sidewalls, a disc mounted for rotarymotion in one of said annular spaces in said casing and having aplurality of equally spaced radially outwardly extending teeth on itsouter periphery positioned to sealingly engage said sidewalls and tomove through said cavities, a ring mounted for rotary motion in theother of said spaces in said casing in a plane oblique to the plane ofmotion of said disc and having a plurality of equally spaced radiallyinwardly extending teeth on the inner periphery positioned in atransverse relation to the direction of motion of said ring to sealinglyengage said sidewalls and to mesh with the teeth on said disc at thepoints of intersection of the plane of motion of said disc and ring,said teeth on said disc being smaller in width than the teeth on saidring, one of said teeth on said ring always being in sealing engagementwith said sidewalls at the said points of intersection to seal thecavities on one side of said points of intersection from the cavities onthe other side of said points of intersection whereby a pressure chamberis formed in the cavity at the point of engagement of said teeth and asuction chamber is formed at the point of disengagement of said teeth.

2. The pump according to claim 1 wherein the inner periphery of theteeth on said ring has a spherical contour, and the outer periphery ofsaid disc between said teeth has a spherical contour corresponding tothe contour on said teeth to form a seal on engagement.

3. The pump according to claim 1 wherein said sidewalls of the other ofsaid spaces at the point of intersection with said one of said spaceshas a length sufficient to bridge the gap between two of the teeth onsaid ring.

4. The pump according to claim 3 wherein said length is equal to thewidth of one gap and the thickness of one tooth.

5. A rotary pump comprising,

a casing having a first pair of sidewalls defining an annular space, asecond pair of sidewalis defining a second annular space, intersectingsaid first annular space at an angle,

a disc mounted for rotary motion in said first annular space and havinga plurality of radially outwardly directed pumping teeth on its outerperiphery,

a ring mounted for rotary motion in said second annular space and havinga plurality of radially inwardly directed sealing teeth on its innerperiphery positioned in a transverse relation to the direction of motionof said ring to sealingly engage said sidewalls, said sealing teethbeing larger in width than said pumping teeth and spaced for meshingengagement with said pumping teeth at the line of intersection of saidannular spaces and being spaced apart a distance greater than the widthof said pumping teeth,

and a cavity in said casing on each side of said line of intersection ofsaid spaces,

one of said sealing teeth always sealingly engaging said sidewalls ofsaid second annular space at the line of intersection of said annularspaces, whereby pressure chambers are formed on one side of the line ofintersection of said spaces and suction chambers are formed on the otherside of said line of intersection.

6. The pump according to claim 5 wherein said disc has a sphericalcontour between said pump teeth and said sealing teeth have a sphericalcontour corresponding to the contour of said disc to form a sealtherebetween.

7. The pump according to claim 5 wherein the sealing surface of saidsidewalls between said cavities bridges the gap between said sealingteeth.

8. The pump according to claim 5, wherein the disc is narrower than thering.

9. The pump according to claim 8 wherein the outer surface secondannular space at an angle, a plurality of pumping teeth of said disc isspherical and the inner surface of said teeth on on said disc mountedfor rotary motion in said third annular said ring is spherical. space,

10. The pump according to claim 5 including a third pair of and te eth nsflid s ing with the p mping e h sidewalls positioned in a spacedrelation to said first pair of on 52nd disc In said 11rd annulal' Psidewalls to define a third annular space intersecting said

1. A rotary pump comprising a casing having a number of cavitiesconnected by annular spaces having sidewalls, a disc mounted for rotarymotion in one of said annular spaces in said casing and having aplurality of equally spaced radially outwardly extending teeth on itsouter periphery positioned to sealingly engage said sidewalls and tomove through said cavities, a ring mounted for rotary motion in theother of said spaces in said casing in a plane oblique to the plane ofmotion of said disc and having a plurality of equally spaced radiallyinwardly extending teeth on the inner periphery positioned in atransverse relation to the direction of motion of said ring to sealinglyengage said sidewalls and to mesh with the teeth on said disc at thepoints of intersection of the plane of motion of said disc and ring,said teeth on said disc being smaller in width than the teeth on saidring, one of said teeth on said ring always being in sealing engagementwith said sidewalls at the said points of intersection to seal thecavities on one side of said points of intersection from the cavities onthe other side of said points of intersection, whereby a pressurechamber is formed in the cavity at the point of engagement of said teethand a suction chamber is formed at the point of disengagement of saidteeth.
 2. The pump according to claim 1 wherein the inner periphery ofthe teeth on said ring has a spherical contour, and the outer peripheryof said disc between said teeth has a spherical contour corresponding tothe contour on said teeth to form a seal on engagement.
 3. The pumpaccording to claim 1 wherein said sidewalls of The other of said spacesat the point of intersection with said one of said spaces has a lengthsufficient to bridge the gap between two of the teeth on said ring. 4.The pump according to claim 3 wherein said length is equal to the widthof one gap and the thickness of one tooth.
 5. A rotary pump comprising,a casing having a first pair of sidewalls defining an annular space, asecond pair of sidewalls defining a second annular space, intersectingsaid first annular space at an angle, a disc mounted for rotary motionin said first annular space and having a plurality of radially outwardlydirected pumping teeth on its outer periphery, a ring mounted for rotarymotion in said second annular space and having a plurality of radiallyinwardly directed sealing teeth on its inner periphery positioned in atransverse relation to the direction of motion of said ring to sealinglyengage said sidewalls, said sealing teeth being larger in width thansaid pumping teeth and spaced for meshing engagement with said pumpingteeth at the line of intersection of said annular spaces and beingspaced apart a distance greater than the width of said pumping teeth,and a cavity in said casing on each side of said line of intersection ofsaid spaces, one of said sealing teeth always sealingly engaging saidsidewalls of said second annular space at the line of intersection ofsaid annular spaces, whereby pressure chambers are formed on one side ofthe line of intersection of said spaces and suction chambers are formedon the other side of said line of intersection.
 6. The pump according toclaim 5 wherein said disc has a spherical contour between said pumpteeth and said sealing teeth have a spherical contour corresponding tothe contour of said disc to form a seal therebetween.
 7. The pumpaccording to claim 5 wherein the sealing surface of said sidewallsbetween said cavities bridges the gap between said sealing teeth.
 8. Thepump according to claim 5, wherein the disc is narrower than the ring.9. The pump according to claim 8 wherein the outer surface of said discis spherical and the inner surface of said teeth on said ring isspherical.
 10. The pump according to claim 5 including a third pair ofsidewalls positioned in a spaced relation to said first pair ofsidewalls to define a third annular space intersecting said secondannular space at an angle, a plurality of pumping teeth on said discmounted for rotary motion in said third annular space, and said teeth onsaid ring meshing with the pumping teeth on said disc in said thirdannular space.